In recent years, technologies relating to vehicles generally used have rapidly changed. For aiming environmental consideration and high efficiency of an engine, a fuel has been developed from gasoline to hybrid, fuel cells, and hydrogen batteries. A large number of resin molded products is used in the interior of vehicles, in order to reduce a weight, and the development of interior decoration of vehicles has been proceeded in accordance with the usage of the resin molded products to change the interior of the vehicles into a comfortable space. Accordingly, decorative objects of the vehicles are extremely highly needed.
Even in such an environment, in-mold molded products are not sufficiently used in the interior of vehicles. This is because that high-strength polycarbonate or the like is used as a resin of the interior of vehicles, but a film for in-molding capable of sufficiently withstanding a molding temperature thereof is not provided and defects of appearance occur in a process of manufacturing a molded product. In addition to the interior of vehicles, polycarbonate or the like is also used as a resin for molding in the exterior of vehicles or the exterior of smart phones, and the same problems described above occur. Hereinafter, a film for in-molding, an in-mold molded product, and a method for manufacturing the same of the related art will be introduced.
FIG. 7 shows a layer configuration of a film for in-molding of the related art. A film for in-molding disclosed in PTL 1 also has the same layer configuration as that of the related art. The film for in-molding is configured with carrier film 401 which is not transferred to an injection molding resin and transfer film 402 which is transferred to the injection molding resin.
Carrier film 401 is configured with base film 403 which is formed of a PET or acrylic film which continuously supplies transfer film 402, and peeling layer 404 for peeling transfer film 402 from base film 403. Transfer film 402 is configured with protective layer or hard coat layer 405, primer layer 406, coloring layer 408, hiding layer 410, and adhesive layer 411. Protective layer or hard coat layer 405 is an outermost surface of an in-mold molded product and has a function of protecting transfer film 402 from scratches or contaminations. Primer layer 406 has a function of connecting protective layer or hard coat layer 405 and coloring layer 408 to each other. Coloring layer 408 includes ink which is an organic material and has a function of applying a color, a pattern, or a design to a surface of an in-mold molded product. Hiding layer 410 has a function of hiding a color of coloring layer 408 and adhesive layer 411 has a function of bonding transfer film 402 to an injection molding resin. As described above the film for in-molding is configured with a plurality of layers.
FIG. 8 schematically shows a method for manufacturing an in-mold molded product of the related art. In the method for manufacturing an in-mold molded product of the related art, film for in-molding 604 described with reference to FIG. 7 is fixed to movable die 606 by using film pressing members 609. Then, film for in-molding 604 is sufficiently shaped so that film for in-molding 604 is sucked by suction holes 608 and bonded to a surface of a die of movable die 606.
After that, a cavity is formed between fixed die 605 and movable die 606 with film for in-molding 604 interposed therebetween, and molten injection molding resin 612 is injected from gate 611 to fill the cavity. After the cavity is filled with injection molding resin 612, injection molding resin 612 is cooled and solidified. When movable die 606 is moved, the transfer film of the film for in-molding is peeled off from the base film and an in-mold molded product in which a transfer film is formed on a surface of injection molding resin 612 is obtained.